After completing a BA in history at the University of Adelaide, Rex Ingamells worked as a teacher, freelance journalist and publisher's representative. Ingamells began writing short stories and poems in 1930, and by 1936 he was seriously exploring the ideas that would establish the Jindyworobak Movement. Ingamells' idea of poetry was influenced by P. R. Stephensen's The Foundations of Culture in Australia (1936), D. H. Lawrence's Kangaroo (1923) and his reading on Aboriginal culture. Ingamells took the word 'Jindy-worabak' from James Devaney's The Vanished Tribes (1929), attracted by Devaney's definition 'to annex, to join'. Ingamells encouraged poetry that avoided European traditions and more closely signified the Australian environment to produce an authentic expression of Australian culture.
While not widely admired for his poetry today, Ingamells attracted some attention in the 1940s, winning the Grace Leven Prize for The Great South Land (1945). The Jindyworobak philosophy attracted a variety of writers, including Flexmore Hudson, Max Harris, Colin Thiele, Judith Wright, Gwen Harwood and Geoffrey Dutton. Between 1938 and 1953 Ingamells produced annual Jindyworobak anthologies and he wrote a history of the movement in 1948. But the movement was sometimes bitterly attacked by mainstream critics and ceased to exist by the end of the 1950s. Nevertheless, critics have detected elements of Jindyworobakism in the works of Xavier Herbert, Patrick White, Peter Porter and Les Murray. In 1951 Ingamells was appointed a judge of the Commonwealth Jubilee Literary Competiton.
Rex Ingamells was killed in a car accident in 1955.